System for control of multiple defibrillation therapies

ABSTRACT

A defibrillation system that includes a first defibrillation device and a second defibrillation device. The first defibrillation device including a therapy module, a communication module, a physiological parameter module and a timing control unit. The second defibrillation device including a therapy module and a communication module. The timing control unit configured to output an instruction to cause the therapy module of the first defibrillator and the therapy module of the second defibrillator to each discharge an energy delivery according to a timing relationship.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/788,671, filed on Oct. 19, 2017, which claims the benefit of U.S.Provisional Patent Application No. 62/410,283, filed on Oct. 19, 2016,the contents of each of which are herein incorporated by reference intheir entirety.

BACKGROUND

Double sequential defibrillation (DSD), also sometimes referred to assimultaneous defibrillation is a recently developed treatment protocolthat is growing in use and popularity to treat patients suffering fromcardiac arrest. For a patient in ventricular fibrillation, andespecially for a patient suffering from recurrent and uncontrolledventricular fibrillation, the use of DSD or simultaneous defibrillationcan be an effective treatment in restoring the patient's normal heartrhythm. DSD is considered by rescuers as a desperate last ditch effortto save the life of a cardiac arrest victim. Administration of DSD canbe haphazard, poorly timed, and uncoordinated. DSD involves simultaneousdefibrillation administered using two separate, same or distinctdefibrillators, such as an automated external defibrillator (AED) and/ora standard defibrillator or monitor/defibrillator. Human rescuers havebeen observed to manually time the two (or more) defibrillation shocksto be delivered to the patient at the same time. Depending on the typeof arrhythmia experienced by the patient, the timing of the shocks isdifferent and the precision with which the shocks must be delivered foreffective treatment is of great importance.

Relying on human ability and/or judgment to administer shocks from twoseparate defibrillators in a coordinated manner is an imperfect systemthat often resulted in ineffective therapy outcomes due to impropershock delivery timing. Improper timing of the shock delivery can alsolengthen the time a patient experiences the cardiac event and treatmentor can cause fatal additional arrhythmias to the patient's heart.

DSD and simultaneous defibrillation is becoming more widely adopted as atreatment for patients suffering from cardiac arrest. Presently, thereis a need for a solution that would assist in properly delivering suchtherapies with precise timing control and reproducible timing ofmultiple shock, or energy deliveries. Further, new systems and/ormethods for safe therapy administration is highly desirable.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram of a scene where an external defibrillator is usedto save the life of a person according to embodiments.

FIG. 2 is a table listing two main types of the external defibrillatorshown in FIG. 1, and who they might be used by.

FIG. 3 is a functional block diagram showing components of an externaldefibrillator, such as the one shown in FIG. 1.

FIG. 4 illustrates an example of a defibrillator with multiple therapymodules.

FIG. 5 illustrates an example of multiple defibrillators with asynchronizing mechanism.

FIGS. 6A-6C illustrate various examples of timing relationships fordelivery of multiple defibrillation shocks.

SUMMARY

An example medical device can include a first therapy module, a secondtherapy module and timing control unit coupled to each. The timingcontrol unit can receive patient data indicative of a shockable heartrhythm and determine at least two energy deliveries based on thereceived data. The two energy deliveries having a timing relationshiprelative to each other. The timing control unit generates instructionsfor the first therapy module to discharge a first energy and for thesecond therapy module to discharge a second energy according to thetiming relationship.

In an example embodiment, a defibrillation device contains the firsttherapy module, the second therapy module and the timing control unit.

In a further example embodiment, the first energy delivery and thesecond energy delivery have a leading edge, a lagging edge and aduration. In an embodiment, the lagging edge of the first energydelivery can substantially coincide with the leading edge of the secondenergy delivery. In a further embodiment, the leading edge of the firstenergy delivery can substantially coincide with the leading edge of thesecond energy delivery.

In another example embodiment, the timing relationship can be determinedautomatically by one or more of the medical device of the timing controlunit. In a further example embodiment, the timing relationship can beselected from one or more predetermined timing relationships.

In an example embodiment, one or more of the first energy delivery, thesecond energy delivery and the timing relationship can be based on oneor more of the patient treatment data or at least one patientphysiological parameter.

In a further example embodiment, the first therapy module and the timingcontrol unit can be in a first medical device and the second therapymodule can be in a second medical device. In another example embodiment,the first device can include a first communication module and the secondmedical device can include a second communication module, with the firstcommunication module communicatively coupled to the second communicationmodule via a communication link. In another example embodiment, thefirst communication module can be coupled to the timing control unit andconfigured to transmit the instruction to the second communicationmodule, via the communication link, to cause the second energy deliveryfrom the second therapy module. In a further example embodiment, thefirst medical device can automatically determine a proximity of thesecond medical device and establish a communication link between thefirst and second medical devices to communicatively couple the timingcontrol unit of the first medical device and the second therapy moduleof the second device. In example embodiments, the communication link canuse a polling protocol or a publish-subscribe protocol.

In an example embodiment, the timing control unit can include aprocessor and memory to store a series of instructions that whenexecuted by the processor cause communication from the timing controlunit to the first therapy module and the second therapy module in apredetermined manner. In another example embodiment, the timing controlunit can include hardware that is configured to cause communicationbetween the timing control unit and the first therapy module and thesecond therapy module in a predetermined manner.

In a further example embodiment, a first pair of electrodes can becoupled to the first therapy module and a second pair of electrodes canbe coupled to the second therapy module. The first pair of electrodescan be configured to transmit at least a portion of the first energydelivery to a patient and the second pair of electrodes can beconfigured to transmit at least a portion of the second energy deliveryto the patient.

An example patient defibrillation system can include a firstdefibrillation device and second defibrillation device. The firstdefibrillation device can include a first therapy module configured tooutput a first energy delivery having a first leading edge, a firstlagging edge and a first duration. The first defibrillation device canalso include a first communication module and physiological parametermodule that is configured to cause a physiological output based on oneor more physiological parameters of a patient. A timing control unit canalso be included in the first defibrillation device and can be coupledto the first therapy module, the first communication module and thephysiological parameter module. The timing control unit can beconfigured to output an instruction in response to the physiologicaloutput and the instruction, based on a timing relationship, can causeoutput of the first energy delivery by the first therapy module and cancause at least a portion of the instruction to be transmitted by thefirst communication module. The second defibrillation device can includea second therapy module configured to output a second energy deliveryhaving a second leading edge, a second lagging edge and a secondduration. The second defibrillation device can also include a secondcommunication module that is communicatively coupled to the firstcommunication module of the first defibrillation device and to thesecond therapy module. The second communication module can receive atleast a portion of the instruction causing output of the second energydelivery by the second energy delivery module, such that one or more ofthe second leading edge, the second lagging edge and the second durationoccurs relative to one or more of the first leading edge, the firstlagging edge and the first duration based on the timing relationship.

In an example embodiment, one or more of the first leading edge, thefirst lagging edge and the first duration of first energy delivery andone or more of the second leading edge, the second lagging edge and thesecond duration can be based on the one or more physiological parametersof the patient.

In a further example embodiment, the at least a portion of theinstruction can include at least one of the second leading edge, thesecond lagging edge and the second duration of the second energydelivery relative to the one or more of the first leading edge, thefirst lagging edge and the first duration.

DETAILED DESCRIPTION

Described herein are methods and systems for controlling multipledefibrillation therapies, such as dual sequential defibrillation (DSD)and simultaneous defibrillation. DSD is the administration of multipledefibrillation therapies, or energy deliveries, the administration ofeach timed relative to one or more preceding administration.Simultaneous defibrillation is the administration of multipledefibrillations, or energy deliveries, substantially concurrently. Theadministration of multiple defibrillations and/or energy therapies hasbeen used to assist with correcting an abnormal heart rhythm of patientcardiac event victim. The systems and methods described below provide acontrolled, adjustable and repeatable means for delivery of suchdefibrillation therapies so as to assist in the correction of anabnormal heart rhythm. FIGS. 1-3 explain a general overview ofdefibrillation therapy using a single defibrillation or therapy modulefor sake of simplifying the general explanation. FIGS. 4-6C relatespecifically to DSD and/or simultaneous defibrillation using two or moretherapy modules and/or defibrillators.

FIG. 1 is a diagram of a defibrillation scene in which a patient isreceiving defibrillation therapy from a single external defibrillator100. The person 82 is lying on his or her back and could be a patient ina hospital, or someone found unconscious, and then turned to be on theirback. The person 82 is experiencing a cardiac arrhythmia in his or herheart 85, which could be Ventricular Fibrillation (VF) for example.

A portable external defibrillator 100 has been brought close to theperson 82. At least two defibrillation electrodes 104, 108 are usuallyprovided with an external defibrillator 100, and are sometimes calledelectrodes 104, 108. The electrodes 104, 108 are coupled with theexternal defibrillator 100 via respective electrode leads 105, 109. Arescuer (not shown) has attached electrodes 104, 108 to the skin ofperson 82 and actuates the defibrillator 100 to administer a brief,strong electric pulse 111 via electrodes 104, 108 through the body ofperson 82. Pulse 111, also known as a defibrillation shock, goes alsothrough heart 85, in an attempt to restart it by depolarizing thecardiac cells and resetting the natural pace for the heart, for savingthe life of the person 82.

The defibrillator 100 can be one of different types, each with differentsets of features and capabilities. The set of capabilities of thedefibrillator 100 is determined by planning who would use it, and thetraining those rescuers would be likely to have. Examples are nowdescribed.

FIG. 2 is a table listing two main types of external defibrillators, andtheir primary users. A first type of defibrillator 100 is generallycalled a defibrillator-monitor because it is typically formed as asingle defibrillation unit in combination with a patient monitor. Adefibrillator-monitor is sometimes called monitor-defibrillator. Adefibrillator-monitor is intended to be used by persons in the medicalprofessions, such as doctors, nurses, paramedics, emergency medicaltechnicians, etc. and often requires technical training on itsoperation. Such a defibrillator-monitor is intended to be used in apre-hospital or hospital scenario.

As a defibrillator, the device can be one of different varieties, oreven versatile enough to be able to switch among different modes thatindividually correspond to the device varieties. One variety is that ofan automated defibrillator, which can determine whether a shock isneeded and, if so, charge a therapy module of the device to apredetermined energy level and instruct and/or prompt the user toadminister the shock. Another variety is that of a manual defibrillatorwhere the user determines the need and controls administering the shock.

As a patient monitor, the device has features additional to what isminimally needed for mere operation as a defibrillator. These featurescan be for monitoring physiological indicators of a person in anemergency scenario. These physiological indicators are typicallymonitored as signals. For example, these signals can include a person'sfull ECG (electrocardiogram) signal or impedance between two electrodes.Additionally, these signals can relate to the person's temperature,non-invasive blood pressure (NIBP), arterial oxygen saturation/pulseoximetry (SpO2), the concentration or partial pressure of carbon dioxidein the respiratory gases, known as capnography, and so on. These signalscan be further stored and/or transmitted as patient data.

A second type of external defibrillator 100 is generally called an AED,which stands for “Automated External Defibrillator”. An AED typicallyautomatically makes the shock/no shock determination on whether todeliver defibrillation therapy to the patient. Indeed, it can senseenough physiological conditions of the person 82 via only the showndefibrillation electrodes 104, 108 of FIG. 1. In its presentembodiments, an AED can either administer the shock automatically, orinstruct the user to do so, e.g. by pushing a button. Being of a muchsimpler construction, an AED typically costs much less than adefibrillator-monitor. As such, hospitals, for example, may deploy AEDsat its various floors, in case the more expensive defibrillator-monitoris more critically being deployed at an Intensive Care Unit or otheremergency situation of greater need, and so on.

AEDs, however, can also be used by people who are not in the medicalprofession. More particularly, an AED can be used by many professionalfirst responders, such as the police, firefighters, emergency medicalpersonnel, etc. AEDs are often found in public locations especiallythose locations that tend to host large numbers of people. Such AEDs areoften operated by rescuers with first-aid training or by a goodSamaritan who has no training on the device at all AEDs increasingly cansupply instructions to whoever is using them and anticipate this widevariety of skill levels of its users.

AEDs are thus particularly useful because clinical response time is verycritical when responding to someone suffering VF. Indeed, the people whoare able to first reach the VF sufferer may not be and are often not inthe medical professions.

There are additional types of external defibrillators that are notlisted in FIG. 2. For example, a hybrid defibrillator can have aspectsof an AED and also of a defibrillator-monitor. A usual such aspect isadditional ECG monitoring capability among others.

FIG. 3 is a diagram showing components of an external defibrillator 300made according to embodiments. These components can be, for example, inthe external defibrillator 100 of FIG. 1. Additionally, the componentsof FIG. 3 can be provided in a housing 301, which can also be known as acasing 301. The external defibrillator 300 is intended for use by a user380, who is the rescuer. The defibrillator 300 typically includes adefibrillation port 310, such as a socket in the housing 301. Thedefibrillation port 310 includes nodes 314, 318. The defibrillationelectrodes 304, 308, which can be similar to the electrodes 104, 108,can be connected to the defibrillation port 310 so as to make anelectrical connection with the nodes 314, 318, respectively. It is alsopossible that electrodes can be connected continuously to thedefibrillation port 310, etc. Either way, the defibrillation port 310can be used for guiding an electrical charge that has been stored in thedefibrillator 300 to the person 82 through the electrodes.

If the defibrillator 300 is a defibrillator-monitor, as was describedwith reference to an example discussed in FIG. 2, then it will typicallyalso have an ECG port 319 in housing 301, for plugging in ECG leads 309.ECG leads 309 can help sense an ECG signal, e.g. a 12-lead signal, orfrom a different number of leads. Moreover, a defibrillator-monitorcould have additional ports (not shown), and another component 325structured to filter the ECG signal, e.g., apply at least one filter tothe signal so as to remove chest compression artifacts resulting fromchest compressions being delivered to the person 82. The defibrillator300 shown in FIG. 3 also includes a measurement circuit 320 thatreceives patient physiological signal(s) from the ECG port 319, and alsofrom other ports, if provided. These physiological signals are sensed,and information about them is rendered by the circuit 320 as data, orother signals, etc.

If the defibrillator 300 is an AED, it may lack an ECG port 319. Themeasurement circuit 320 can obtain physiological signals through nodes314, 318 instead, when defibrillation electrodes 304, 308 are attachedto person 82. In these examples, a patient's ECG signal can be sensed asa voltage difference between the electrodes 304, 308. Further, impedancevalues sensed between the electrodes 304, 308 can be detect, among otherthings, whether these electrodes 304, 308 have been inadvertentlydisconnected from the person.

The defibrillator 300 also includes a processor 330 that may beimplemented in any number of ways. Such ways include, by way of exampleand not limitation, digital and/or analog processors such asmicroprocessors and digital-signal processors (DSPs); controllers suchas microcontrollers; software running in a machine; programmablecircuits such as Field Programmable Gate Arrays (FPGAs),Field-Programmable Analog Arrays (FPAAs), Programmable Logic Devices(PLDs), Application Specific Integrated Circuits (ASICs), anycombination of one or more of these, and so on.

The processor 330 can be include a number of modules. One such module isa detection module 332, which senses outputs of measurement circuit 320.Detection module 332 can include a VF detector. Thus, the person'ssensed ECG can be used to determine whether the person is experiencingVF. Another such module in the processor 330 is an advice module 334,which arrives at advice based on output(s) of the detection module 332.Advice module 334 can include a Shock Advisory Algorithm, implementdecision rules, and so on. The advice can be to shock, to not shock, toadminister other forms of therapy, and so on. If the advice is to shock,some external defibrillator embodiments merely report the shockrecommendation to the user, and prompt them to do it. Other embodimentsfurther execute the advice, by administering the shock. If the advice isto administer CPR, the defibrillator 300 may further issue prompts forit, and so on. The processor 330 can include additional modules, such asthe module 336, for other functions. In addition, if another component325 is indeed provided, it may be operated in part by the processor 330,etc.

Defibrillator 300 optionally further includes a memory 338, which canwork together with the processor 330. The memory 338 may be implementedin any number of ways. Such ways include, by way of example and not oflimitation, nonvolatile memories (NVM), read-only memories (ROM), randomaccess memories (RAM), any combination of these, and so on. The memory338, if provided, can include programs for the processor 330, and so on.The programs can be operational for the inherent needs of the processor330, and can also include protocols and ways that decisions can be madeby the advice module 334. In addition, the memory 338 can store promptsfor the user 380 and patient data, as needed.

The defibrillator 300 may also include a power source 340. To enableportability of the defibrillator 300, the power source 340 typicallyincludes a battery. Such a battery can be implemented as a battery pack,which may be rechargeable or not. Sometimes, a combination is used, ofrechargeable and non-rechargeable battery packs. Other embodiments ofpower source 340 can include AC power override that allows a rescuer touse AC power when such a source exists, but rely on the battery power ifAC power is unavailable. In some embodiments, the power source 340 iscontrolled by the processor 330. The defibrillator 300 additionallyincludes an energy storage module 350. The module 350 is where someelectrical energy is stored, when preparing the device for suddendischarge to administer defibrillation shock therapy to the patient. Themodule 350 can be charged from the power source 340 to the desiredamount of energy, as controlled by the processor 330. In typicalimplementations, the module 350 includes one or more capacitors 352 thatcharge and help store the energy for later discharge, and so on.

The defibrillator 300 can also include a discharge circuit 355. Thedischarge circuit 355 can be controlled to permit the energy stored inthe module 350 for discharge to the nodes 314, 318, and thus also to thedefibrillation electrodes 304, 308. The discharge circuit 355 caninclude one or more switches 357. Those switches can be made in a numberof ways, such as by an H-bridge, and so on, or other desirableconfigurations.

The defibrillator 300 further includes a user interface 370 for the user380. For example, the interface 370 may include a screen to display whatis detected and measured, provide visual feedback to the rescuer fortheir resuscitation attempts, and so on. The interface 370 may alsoinclude a speaker to issue voice prompts or otherwise audibly interactwith the user and may additionally include various controls, such aspushbuttons, keyboards, and so on, as needed or desired. In addition,the discharge circuit 355 can be controlled by the processor 330, ordirectly by the user 380 through the user interface 370.

The defibrillator 300 can optionally include other components. Forexample, a communication module 390 may be provided for communicatingwith other machines. Such communication can be performed wirelessly, orvia wire, or by infrared communication, and so on. This way, data can becommunicated, such as patient data, incident information, therapyattempted, CPR performance, and the like. Another feature of adefibrillator can be CPR-prompting in which prompts are issued to theuser, visual or by sound or otherwise, so that the user can administerCPR and/or receive feedback/instructions regarding the administration ofCPR and/or delivery of shock therapy to the patient.

FIG. 4 shows an example defibrillator 400 capable of delivering DSDand/or simultaneous defibrillation therapy to a patient. Thedefibrillator 400 includes a timing control unit 410, a physiologicalparameter module 450 and two therapy modules 420 a, 420 b that areconnected to respective electrodes 430 a, 430 b. Any suitable number oftherapy modules and respective electrodes could be used in alternativeconfigurations. In this example, the defibrillator has a single housingthat includes each of the timing control unit 410, the physiologicalparameter module 450, and the two therapy modules 420 a, 420 b, e.g.,the defibrillator 400 is a single medical device. The defibrillator 400can be connected to a patient through the electrodes 430 a, 430 b andcan receive various patient data relevant to applying a custom treatmentprotocol, such as patient physiological data, to monitor the patient andto determine the presence of a shockable heart rhythm. In response to ashockable heart rhythm and/or an instruction to deliver a shock, thetherapy modules 420 a, 420 b, when triggered via instructions from thetiming control unit 410, can deliver an energy discharge to a patientthrough electrodes 430 a, 430 b. The energy discharge is adefibrillation shock or shock therapy that helps reset the heart'snormal electrical activity.

Patient physiological or treatment data can be received by the patientphysiological module, if one is present. 450 of the defibrillator 400from one or more sensors and/or systems, such as a patient monitor.Electrocardiogram (ECG) data can be included in the patientphysiological data to provide data regarding the functioning of apatient's heart, such as a heart rhythm. The patient physiologicalmodule 450, or other system, can analyze the received patientphysiological data to determine if an energy delivery to the patient isappropriate and/or necessary. In response to determining that such anenergy delivery should occur, the physiological parameter module 450 cancause the timing control unit 410 to generate and/or transmitinstructions to the therapy modules 420 a, 420 b to deliver energy tothe patient based on a selected and/or calculated timing relationshipbetween the two therapy modules 420 a, 420 b.

The timing control unit 410 is electrically connected to each of thetherapy modules 420 a, 420 b and generates instructions to control theenergy discharge and/or delivery of shock therapy from one or both ofthe therapy modules 420 a, 420 b. Based on the patient treatment datareceived by the defibrillator 400, the timing control unit 410 cangenerate instructions for the therapy modules 420 a, 420 b to coordinatethe energy delivery from each module with respect to each other'stherapy delivery. The instructions can include various characteristicsof the energy delivery from each of the therapy modules 420 a, 420 b,such as the timing of the energy delivery, an amount of energy todeliver and/or other energy delivery characteristics.

The timing of the energy delivery from each of the therapy modules 420a, 420 b can be coordinated such that the total energy delivery from thetherapy modules 420 a, 420 b is delivered as desired, or required, suchas to deliver an effective defibrillation shock therapy to a patient'sheart. The timing unit 410 instructions can cause the energy deliveryfrom each of the therapy modules 420 a, 420 b to be precisely deliveredsuch that each delivery substantially overlaps each other, partiallyoverlaps or does not overlap at all. The coordinated energy deliveryfrom the therapy modules 420 a, 420 b can result in a more effectivetreatment of a shockable heart rhythm of a patient.

As mentioned above, the timing control unit 410 can transmitinstructions to the therapy modules 420 a, 420 b to cause energydelivery from each of the therapy modules 420 a, 420 b. The transmissionof the instructions can be effected by a software messaging mechanism,digital trigger and/or other triggering means to cause the energydelivery from the therapy modules 420 a, 420 b in a coordinated manner.In a further embodiment, each of the therapy modules 420 a, 420 b can beconnected to a separate timing control unit. One or more of the timingcontrol units can communicate with, or otherwise provide information to,the other timing control units to cause the coordinated energy deliveryfrom each of the therapy modules 420 a, 420 b, as based on the timingrelationship.

Each therapy module 420 a, 420 b, and/or the defibrillator 400, caninclude an isolation relay, or relays, to isolate one or more of thedefibrillator 400, and/or therapy modules 420, 420 b, from feedbackcaused by an energy delivery. The isolation relay can prevent feedbackfrom an energy delivery of a therapy module into one or more othertherapy modules.

The defibrillator 400, as shown in FIG. 4, is a single unit with twotherapy modules 420 a, 420 b housed within. While shown as two separateelements, the therapy modules 420 a, 420 b can also besubmodules/subdivisions of a single therapy module. Alternatively, thetwo therapy modules 420 a, 420 b can be separated and integrated into asingle therapy module. In a further embodiment, the defibrillator 400can include a single therapy module capable of multiple, coordinatedenergy deliveries.

The electrodes 430 a, 430 b are similarly shown as separate elements inFIG. 4; however, the therapy modules 420 a, 420 b can be connected to asingle electrode pair for energy delivery to a patient. In anembodiment, the defibrillator 400 can include connections to associatean electrode pair with each of the therapy modules, as shown in FIG. 4,and a connection that allows a single pair of electrodes to facilitateenergy delivery from each therapy module of the defibrillator.

Alternatively, the timing relationship between the energy delivery byeach of the therapy modules 420 a, 420 b can be based on sensing anenergy delivery by one or more of the therapy modules 420 a, 420 b. Forexample, a first therapy module 420 a can output a first energydelivery, the first energy delivery can be detected by a second therapymodule 420 b through second electrodes 430 b. Sensing the first energydelivery, the second therapy module 420 b can output a second energydelivery based on the sensed first energy delivery, in a predeterminedmanner and/or other timing relationship.

FIG. 5 illustrates an example pair of separate and distinctdefibrillators 500 a, 500 b that capable of a coordinated energydelivery of multiple defibrillation shock therapy based on a precisetiming relationship. In the example shown, two defibrillators 500 a, 500b communicate with each other to coordinate energy delivery from each oftheir respective therapy modules 520 a, 520 b based on a timingrelationship. Each of the defibrillators 500 a, 500 b include acommunication module 540 a, 540 b and a therapy module 520 a, 520 b,connected to electrodes 530 a, 530 b. One or more of the defibrillators500 a, 500 b also includes a timing control unit 510 a, 510 b thatcoordinates the energy delivery from each of the therapy modules 520 a,520 b of the defibrillators 500 a, 500 b.

The communication module 540 a, 540 b of each defibrillator 500 a, 500b, communicates with their respective counterpart through a connection545 that can be a wired and/or wireless connection. The wirelessconnection can include a direct wireless connection between thedefibrillators 500 a, 500 b, and/or a wireless connection through alarger network. Further, the combination between the defibrillators 500a, 500 b can use a combination of wired and wireless connections and/ornetworks. Example wireless connection can include infrared, radio,Bluetooth®, Wi-Fi and/or other communication networks. The communicationmodules 540 a, 540 b can also be configured to communicate any data to alarger computing platform, such as a comprehensive network of connectedpoints-of-care along a treatment pathway or among multiple connectedtreatment pathways. The communication modules 540 a, 540 b can alsoconnect to remote locations as well, such as a hospital or advice centerto aid the care team both at the instant point-of-care and at the nextpoint-of-care along the treatment pathway.

Data, such as patient physiological data and/or a timing relationship,can be communicated from one defibrillator 500 a, 500 b to anotherdefibrillator 500 a, 500 b via the connection 545. For a timingrelationship, the data exchanged and/or transmitted can include a clocksignal to synchronize the defibrillators 500 a, 500 b, a trigger tocause one or more of the defibrillators 500 a, 500 b to deliver energyto the patient, a timed delay for delivery of energy from the receivingdefibrillator 500 a, 500 b and/or other timing relationship informationnecessary to coordinate the delivery of energy from the defibrillators500 a, 500 b based on a timing relationship.

Various communication protocols and/or styles can be used to effectcommunication between the two or more defibrillators 500 a, 500 b.Example communications can include polling and/or publish-subscribe. Ina polling arrangement, one of the defibrillators 500 a, 500 b acts as amaster and the remaining defibrillators are slaves. The masterdefibrillator broadcasts the message, or data, to all of the slavedefibrillators and can then poll each defibrillator in turn to receive aresponse and/or other information. In a publish-subscribe arrangementeach defibrillator can publish a message, or data, that is tagged withone or more categories and subscriber defibrillators receive and processthe message if the category of the published message, or data, matchesone they are monitoring. Alternatively, the defibrillators 500 a, 500 bcan use other messaging and/or data transmission protocols to exchangeinformation and/or data, such as a timing relationship.

In an example embodiment, both defibrillators 500 a, 500 b can include atiming control unit 510 a, 510 b that transmits instructions for energydelivery to the respective therapy module 520 a, 520 b coupled thereto.In this arrangement, one of the defibrillators 500 a, 500 b can act as aprimary defibrillator that transmit instructions to the other one ormore defibrillators 500 a, 500 b to cause the delivery of energy to thepatient based on a timing relationship. The primary defibrillator cantransmit the selected and/or calculated timing relationship, or data, tothe other, secondary, defibrillator via the connection 545.Additionally, the timing relationship can include a clock or othersignal to synchronize the various timing elements of each of thedefibrillators 500 a, 500 b. In response to the received timingrelationship, the communication module 540 a, 540 b and/or the timingcontrol unit 510 a, 510 b, of the secondary defibrillator can transmitinstructions to and/or cause the therapy module 520 a, 520 b of thesecondary defibrillator to deliver energy to the patient based on thetiming relationship.

In an alternative embodiment, the secondary defibrillator 500 a, 500 bcan be a secondary device that can communicate with the primarydefibrillator 500 a, 500 b and deliver energy to a patient whentriggered and/or instructed to do so. In this manner, the secondarydevice can be a “dumb” device that is only capable of energy deliverywhen triggered, and cannot perform patient physiological dataacquisition and/or analysis. The “dumb” nature of the secondary devicecan reduce the required complexity and/or cost of the secondary deviceneeded to cause the synchronized delivery of multiple energies.

In an example, a “dumb” device could include older model defibrillatorsthat lack one or more abilities of newer and/or more currentdefibrillators. The older defibrillators can be modified and/or equippedwith a communication module, or means, allowing them to be used for thecoordinated delivery of energy to the patient as described herein.

FIGS. 6A-6C illustrate example timing relationships for delivery ofenergy from one or more therapy modules 610, 620 of one or more devices,such as a defibrillator of FIG. 4 or the multiple defibrillators of FIG.5. Each energy delivery has a leading edge, or beginning/initiation, ofan energy delivery and a lagging edge, or ending/termination, of theenergy delivery. The various timing relationships can be based on therelative timing between the various leading and/or lagging edges of theone or more energy deliveries. Patients suffering from some cardiacarrhythmias, specifically persistent VF, for example, respond well toeither or both of an increase in the time duration and/or the magnitudeof the energy delivery.

In the example of FIG. 6A, a first energy delivery from a first therapymodule 610 has a leading edge 610 a, a lagging edge 610 b and a firstduration that spans between the edges of the first energy delivery. Asecond energy delivery from a second therapy module 620 has a leadingedge 620 a, a lagging edge 620 b and a second duration that spansbetween the edges of the second energy delivery. While the magnitudesand/or durations of the various first and second energy deliveries shownin FIGS. 6A-6C are shown as substantially the same, the magnitude and/orduration of the first and second energy deliveries can be substantiallythe same or different, based on the patient physiological/treatment dataand/or as required/desired. DSD therapy has been shown to be effectivefor correcting cardiac arrhythmias by one or both of lengthening theamount of time the shock therapy is being delivered to the patientand/or by increasing the magnitude of energy delivered to the patient.

In the example timing relationship shown in FIG. 6A, the second energydelivery from the second therapy module 620 is timed so that the leadingedge 620 a of the second energy delivery substantially coincides orimmediately precedes the lagging edge 610 b of the first energydelivery. This timing arrangement causes the first and second energydeliveries to be substantially continuous or occur closely spaced apart.Further, while the first energy delivery by the first therapy module 610is shown as occurring prior to the second energy delivery by the secondtherapy module 620, the occurrence and/or timing of the first and secondenergy deliveries can be switched, with the leading edge 610 a of thefirst energy delivery being closely spaced to or occurring substantiallysimultaneously as the lagging edge 620 b of the second energy delivery.The back-to-back delivery of the shock therapies lengthens the timeduration of the delivery to the patient's heart and may help reset itnatural rhythm.

In the example of FIG. 6B, the first and second energy deliveries areshown as overlapping. The leading edge 610 a of the first energydelivery of the first therapy module 610 is shown as occurring prior tothe lagging edge 620 b of the second energy delivery of the secondtherapy module 620. Such overlap between the two energy deliveriescauses a peak of shock during the time duration of the overlap withshock before and after either being approximately equal in magnitude orvarying, depending on the configuration and therapy protocol. Deliveryof energy in such a manner can be advantageous if the leading and/orlagging edges of one or more of the energy deliveries has slope to, orfrom, the ultimate magnitude of the energy delivery. The overlappingdelivery of the shock therapies lengthens the overall time that thepatient receives the shock therapy and creates a peak magnitude of anincrease of energy in the middle of the delivery of the two shocktherapies.

In the example of FIG. 6C, the first and second energy deliveries areshown as occurring substantially simultaneously. The leading edge 610 aof the first energy delivery by the first therapy module 610substantially coincides, or occurs with, the leading edge 620 a of thesecond energy delivery by the second therapy module 620. In the exampleshown, the lagging edges 610, 620 b of the first and second energies arealso shown as substantially coinciding as the first and second energieshave substantially the same duration. In other embodiments, the durationof the first and second energy deliveries can be different such that thelagging edges 610 b, 620 b of the energy deliveries do not coincide.Alternatively, the leading edges 610 a, 620 a of the energy deliveriesmay occur at different times and the lagging edges 610 b, 620 b of theenergy deliveries can be coincident. The simultaneous or nearsimultaneous delivery of the two shock therapies increases the magnitudeof the energy delivered to the patient but does not lengthen orsubstantially change the length of the duration of the shock therapydelivery.

The timing of the delivery of both of the energy deliveries shown ineach of the timing relationship configurations shown in FIGS. 6A-6C canbe timed precisely with various segments of a patient's ECG signal, ifthe ECG signal is being sensed during the shock therapy. Specifically,the timing relationship may increase the duration and/or the magnitudeof the energy deliveries in persistent VF for example and can becustomized to other cardiac arrhythmias as needed.

The timing control unit of one or more defibrillators can use a timingrelationship, such as those described above, to coordinate the deliveryof multiple shocks and/or energies to a patient. Various characteristicsof the energy delivery, such as a leading edge, lagging edge and/orduration, can be used to time the energy deliveries relative to eachother of a synchronized clock or timing. Further, while the examplesabove are shown with two therapy modules, defibrillators and/or devices,additional therapy modules, defibrillators and/or device can be used todeliver multiple energies to a patient in a coordinated manner based onone or more timing relationships between the energy deliveries.

It will be appreciated that variants of the above-disclosed and otherfeatures and functions, or alternatives thereof, may be combined intomany other different systems or applications. Other embodiments Variouspresently unforeseen or unanticipated alternatives, modifications,variations, or improvements therein may be subsequently made by thoseskilled in the art which are also intended to be encompassed by thefollowing claims.

The invention claimed is:
 1. A defibrillation system, comprising: afirst external defibrillator, comprising: a physiological parametermodule configured to receive electrocardiogram (ECG) data of a patientand to determine, based on the ECG data, that a heart of the patient isexhibiting a shockable rhythm; a timing control unit configured todetermine, based on the ECG data, a timing relationship between a firstdefibrillation shock and a second defibrillation shock; a firstcommunication module configured to transmit an instruction indicatingthe timing relationship; and a first therapy module configured to outputthe first defibrillation shock to the patient; and a second externaldefibrillator, comprising: a second communication module configured toreceive the instruction from the first external defibrillator; and asecond therapy module configured to output, based on the timingrelationship, a leading edge of the second defibrillation shock to thepatient at a different time than a lagging edge of the firstdefibrillation shock.
 2. The defibrillation system of claim 1, whereinthe different time is subsequent to the lagging edge of the firstdefibrillation shock.
 3. The defibrillation system of claim 1, whereinthe different time is prior to the lagging edge of the firstdefibrillation shock.
 4. The defibrillation system of claim 1, whereinthe first external defibrillator further comprises: first electrodescoupled to skin of the patient; and a first discharge circuit configuredto output the first defibrillation shock to the first electrodes, andwherein the second external defibrillator further comprises: secondelectrodes coupled to the skin of the patient; and a second dischargecircuit configured to output the second defibrillation shock to thesecond electrodes.
 5. The defibrillation system of claim 1, wherein eachof a first magnitude of the first defibrillation shock and a secondmagnitude of the second defibrillation shock is smaller than a combinedmagnitude of the first defibrillation shock and the seconddefibrillation shock occurring prior to a lagging edge of the seconddefibrillation shock and after a leading edge of the firstdefibrillation shock.
 6. A primary defibrillator, comprising: a timingcontrol unit configured to determine a timing relationship between afirst defibrillation shock and a second defibrillation shock; acommunication module configured to transmit an instruction to asecondary defibrillator, the instruction indicating the timingrelationship and causing the secondary defibrillator to output thesecond defibrillation shock based on the timing relationship; and atherapy module configured to output the first defibrillation shock, alagging edge of the first defibrillation shock being at a different timethan a leading edge of the second defibrillation shock.
 7. The primarydefibrillator of claim 6, wherein the instruction causes the secondarydefibrillator to output the second defibrillation shock subsequent tothe lagging edge of the first defibrillation shock.
 8. The primarydefibrillator of claim 6, wherein each of a first magnitude of the firstdefibrillation shock and a second magnitude of the second defibrillationshock is smaller than a combined magnitude of the first defibrillationshock and the second defibrillation shock occurring after the leadingedge of the second defibrillation shock and prior to the lagging edge ofthe first defibrillation shock.
 9. The primary defibrillator of claim 6,wherein the therapy module comprises a discharge circuit configured tooutput the first defibrillation shock to electrodes that are coupled toa patient.
 10. The primary defibrillator of claim 6, wherein thecommunication module is configured to transmit the instruction over awired or a wireless connection with the secondary defibrillator.
 11. Theprimary defibrillator of claim 6, further comprising: a measurementcircuit configured to receive an electrocardiogram (ECG) signal of apatient and to identify a shockable rhythm based on the ECG signal,wherein the timing control unit is configured to determine the timingrelationship based on the shockable rhythm.
 12. The primarydefibrillator of claim 11, wherein the shockable rhythm comprisespersistent ventricular fibrillation (VF).
 13. The primary defibrillatorof claim 6, wherein each of a first magnitude of the firstdefibrillation shock and a second magnitude of the second defibrillationshock is smaller than a combined magnitude of the first defibrillationshock and the second defibrillation shock occurring prior to a laggingedge of the second defibrillation shock and after a leading edge of thefirst defibrillation shock.
 14. A method, comprising: determining, basedat least in part on physiological data of a patient, that a heart of thepatient is exhibiting a shockable rhythm; determining a timingrelationship between a first defibrillation shock and a seconddefibrillation shock based, at least in part, on the physiological data;causing a first therapy module of a first defibrillator to discharge thefirst defibrillation shock to the patient in accordance with the timingrelationship; and causing a second therapy module of a seconddefibrillator to discharge the second defibrillation shock to thepatient in accordance with the timing relationship, a leading edge ofthe second defibrillation shock being at a different time than a laggingedge of the first defibrillation shock.
 15. The method of claim 14,wherein the physiological data comprises an electrocardiogram (ECG)measurement, a blood pressure measurement, a pulse oximetry measurement,or a capnography measurement.
 16. The method of claim 14, wherein thedifferent time is subsequent to the lagging edge of the firstdefibrillation shock.
 17. The method of claim 14, wherein the differenttime is prior to the lagging edge of the first defibrillation shock. 18.The method of claim 17, wherein causing the first therapy module todischarge the first defibrillation shock in accordance with the timingrelationship comprises causing the first therapy module to discharge thefirst defibrillation shock to the patient, wherein causing the secondtherapy module to discharge the second defibrillation shock inaccordance with the timing relationship comprises causing the secondtherapy module to discharge the second defibrillation shock to thepatient, and wherein a peak energy delivered to the patient occurs afterthe leading edge of the second defibrillation shock and before thelagging edge of the first defibrillation shock.
 19. The method of claim14, wherein the method is performed by the first defibrillator, andwherein causing the second therapy module to discharge the seconddefibrillation shock in accordance with the timing relationshipcomprises transmitting an instruction to the second defibrillator over awired or a wireless connection.
 20. The method of claim 14, wherein eachof a first magnitude of the first defibrillation shock and a secondmagnitude of the second defibrillation shock is smaller than a combinedmagnitude of the first defibrillation shock and the seconddefibrillation shock occurring prior to a lagging edge of the seconddefibrillation shock and after a leading edge of the firstdefibrillation shock.